OAK RIDGE, Tenn. (WVLT) -- An Oak Ridge senior was sentenced to just over eight years for knowingly possessing child pornography, the U.S. Sept. of Justice announced on Tuesday. After he is released, George Russell will have to spend the rest of his life on supervised release and will be required to participate in a program of sex offender mental health treatment.

The Dept. of Justice said Russell had an "extensive collection" of child pornography, which he posted online in order to trade it. The collection was discovered during an online, undercover investigation by the FBI.

The agents raided the 65 year-old's home and seized his computers they found over 3,800 images and 33 videos of suspected child pornography, according to the Dept. of Justice. The National Center for Missing and Exploited Children identified 48 known victims of child pornography among his collection